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Wang T, Pfeiffer T, Akyildiz A, van Beusekom HMM, Huber R, van der Steen AFW, van Soest G. Intravascular optical coherence elastography. BIOMEDICAL OPTICS EXPRESS 2022; 13:5418-5433. [PMID: 36425628 PMCID: PMC9664873 DOI: 10.1364/boe.470039] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/30/2022] [Accepted: 08/31/2022] [Indexed: 05/07/2023]
Abstract
Optical coherence elastography (OCE), a functional extension of optical coherence tomography (OCT), visualizes tissue strain to deduce the tissue's biomechanical properties. In this study, we demonstrate intravascular OCE using a 1.1 mm motorized catheter and a 1.6 MHz Fourier domain mode-locked OCT system. We induced an intraluminal pressure change by varying the infusion rate from the proximal end of the catheter. We analysed the pixel-matched phase change between two different frames to yield the radial strain. Imaging experiments were carried out in a phantom and in human coronary arteries in vitro. At an imaging speed of 3019 frames/s, we were able to capture the dynamic strain. Stiff inclusions in the phantom and calcification in atherosclerotic plaques are associated with low strain values and can be distinguished from the surrounding soft material, which exhibits elevated strain. For the first time, circumferential intravascular OCE images are provided side by side with conventional OCT images, simultaneously mapping both the tissue structure and stiffness.
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Affiliation(s)
- Tianshi Wang
- Thoraxcentre, Erasmus University Medical Centre, Rotterdam 3015 AA, The Netherlands
| | - Tom Pfeiffer
- Institut für Biomedizinische Optik, Universität zu Lübeck, Lübeck 23562, Germany
| | - Ali Akyildiz
- Thoraxcentre, Erasmus University Medical Centre, Rotterdam 3015 AA, The Netherlands
- Department of Biomechanical Engineering, Delft University of Technology, Delft 2600 AA, The Netherlands
| | | | - Robert Huber
- Institut für Biomedizinische Optik, Universität zu Lübeck, Lübeck 23562, Germany
| | - Antonius F. W. van der Steen
- Thoraxcentre, Erasmus University Medical Centre, Rotterdam 3015 AA, The Netherlands
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518005, China
- Department of Imaging Science and Technology, Delft University of Technology, Delft 2600 AA, The Netherlands
| | - Gijs van Soest
- Thoraxcentre, Erasmus University Medical Centre, Rotterdam 3015 AA, The Netherlands
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2
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Chang S, Handwerker J, Giannico GA, Chang SS, Bowden AK. Birefringent tissue-mimicking phantom for polarization-sensitive optical coherence tomography imaging. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:JBO-210279SSR. [PMID: 35064658 PMCID: PMC8781524 DOI: 10.1117/1.jbo.27.7.074711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 12/22/2021] [Indexed: 06/14/2023]
Abstract
SIGNIFICANCE Tissue birefringence is an important parameter to consider when designing realistic, tissue-mimicking phantoms. Options for suitable birefringent materials that can be used to accurately represent tissue scattering are limited. AIM To introduce a method of fabricating birefringent tissue phantoms with a commonly used material-polydimethylsiloxane (PDMS)-for imaging with polarization-sensitive optical coherence tomography (PS-OCT). APPROACH Stretch-induced birefringence was characterized in PDMS phantoms made with varying curing ratios, and the resulting phantom birefringence values were compared with those of biological tissues. RESULTS We showed that, with induced birefringence levels up to 2.1 × 10 - 4, PDMS can be used to resemble the birefringence levels in weakly birefringent tissues. We demonstrated the use of PDMS in the development of phantoms to mimic the normal and diseased bladder wall layers, which can be differentiated by their birefringence levels. CONCLUSIONS PDMS allows accurate control of tissue scattering and thickness, and it exhibits controllable birefringent properties. The use of PDMS as a birefringent phantom material can be extended to other birefringence imaging systems beyond PS-OCT and to mimic other organs.
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Affiliation(s)
- Shuang Chang
- Vanderbilt University, Vanderbilt Biophotonics Center, Department of Biomedical Engineering, Nashville, Tennessee, United States
| | - Jessica Handwerker
- Vanderbilt University, Vanderbilt Biophotonics Center, Department of Biomedical Engineering, Nashville, Tennessee, United States
| | - Giovanna A. Giannico
- Vanderbilt University Medical Center, Department of Pathology, Microbiology, and Immunology, Nashville, Tennessee, United States
| | - Sam S. Chang
- Vanderbilt University Medical Center, Department of Urology, Nashville, Tennessee, United States
| | - Audrey K. Bowden
- Vanderbilt University, Vanderbilt Biophotonics Center, Department of Biomedical Engineering, Nashville, Tennessee, United States
- Vanderbilt University, Department of Electrical and Computer Engineering, Nashville, Tennessee, United States
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Porous Phantoms Mimicking Tissues-Investigation of Optical Parameters Stability Over Time. MATERIALS 2021; 14:ma14020423. [PMID: 33467152 PMCID: PMC7829841 DOI: 10.3390/ma14020423] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/11/2021] [Accepted: 01/13/2021] [Indexed: 11/17/2022]
Abstract
Optical phantoms are used to validate optical measurement methods. The stability of their optical parameters over time allows them to be used and stored over long-term periods, while maintaining their optical parameters. The aim of the presented research was to investigate the stability of fabricated porous phantoms, which can be used as a lung phantom in optical system. Measurements were performed in multiple series with an interval of 6 months, recreating the same conditions and using the same measuring system consisting of an integrating sphere, a coherent light source with a wavelength of 635 nm and a detector. Scattering and absorption parameters were determined on the basis of the measured reflectance and transmittance. The tested samples were made of silicone and glycerol in various proportions.
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Elyas E, Grimwood A, Erler JT, Robinson SP, Cox TR, Woods D, Clowes P, De Luca R, Marinozzi F, Fromageau J, Bamber JC. Multi-Channel Optical Coherence Elastography Using Relative and Absolute Shear-Wave Time of Flight. PLoS One 2017; 12:e0169664. [PMID: 28107368 PMCID: PMC5249105 DOI: 10.1371/journal.pone.0169664] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 12/20/2016] [Indexed: 11/18/2022] Open
Abstract
Elastography, the imaging of elastic properties of soft tissues, is well developed for macroscopic clinical imaging of soft tissues and can provide useful information about various pathological processes which is complementary to that provided by the original modality. Scaling down of this technique should ply the field of cellular biology with valuable information with regard to elastic properties of cells and their environment. This paper evaluates the potential to develop such a tool by modifying a commercial optical coherence tomography (OCT) device to measure the speed of shear waves propagating in a three-dimensional (3D) medium. A needle, embedded in the gel, was excited to vibrate along its long axis and the displacement as a function of time and distance from the needle associated with the resulting shear waves was detected using four M-mode images acquired simultaneously using a commercial four-channel swept-source OCT system. Shear-wave time of arrival (TOA) was detected by tracking the axial OCT-speckle motion using cross-correlation methods. Shear-wave speed was then calculated from inter-channel differences of TOA for a single burst (the relative TOA method) and compared with the shear-wave speed determined from positional differences of TOA for a single channel over multiple bursts (the absolute TOA method). For homogeneous gels the relative method provided shear-wave speed with acceptable precision and accuracy when judged against the expected linear dependence of shear modulus on gelatine concentration (R2 = 0.95) and ultimate resolution capabilities limited by 184μm inter-channel distance. This overall approach shows promise for its eventual provision as a research tool in cancer cell biology. Further work is required to optimize parameters such as vibration frequency, burst length and amplitude, and to assess the lateral and axial resolutions of this type of device as well as to create 3D elastograms.
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Affiliation(s)
- Eli Elyas
- CRUK Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research, Sutton, Surrey, United Kingdom
- Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom
| | - Alex Grimwood
- Department of Medical Physics, Royal Surrey County Hospital, Guildford, Surrey, United Kingdom
| | - Janine T. Erler
- Biotech Research & Innovation Centre, University of Copenhagen, Copenhagen, Denmark
| | - Simon P. Robinson
- CRUK Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research, Sutton, Surrey, United Kingdom
| | - Thomas R. Cox
- Biotech Research & Innovation Centre, University of Copenhagen, Copenhagen, Denmark
| | - Daniel Woods
- Michelson Diagnostics, 1 Grays Farm Production Village, Orpington, Kent, United Kingdom
| | - Peter Clowes
- Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom
| | - Ramona De Luca
- CRUK Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research, Sutton, Surrey, United Kingdom
- Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom
- Department of Mechanical and Aerospace Engineering, Sapienza University of Rome, Rome, Italy
| | - Franco Marinozzi
- Department of Mechanical and Aerospace Engineering, Sapienza University of Rome, Rome, Italy
| | - Jérémie Fromageau
- CRUK Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research, Sutton, Surrey, United Kingdom
- Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom
| | - Jeffrey C. Bamber
- CRUK Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research, Sutton, Surrey, United Kingdom
- Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom
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Ahmad A, Kim J, Sobh NA, Shemonski ND, Boppart SA. Magnetomotive optical coherence elastography using magnetic particles to induce mechanical waves. BIOMEDICAL OPTICS EXPRESS 2014; 5:2349-61. [PMID: 25071969 PMCID: PMC4102369 DOI: 10.1364/boe.5.002349] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 06/09/2014] [Accepted: 06/11/2014] [Indexed: 05/08/2023]
Abstract
Magnetic particles are versatile imaging agents that have found wide spread applicability in diagnostic, therapeutic, and rheology applications. In this study, we demonstrate that mechanical waves generated by a localized inclusion of magnetic nanoparticles can be used for assessment of the tissue viscoelastic properties using magnetomotive optical coherence elastography. We show these capabilities in tissue mimicking elastic and viscoelastic phantoms and in biological tissues by measuring the shear wave speed under magnetomotive excitation. Furthermore, we demonstrate the extraction of the complex shear modulus by measuring the shear wave speed at different frequencies and fitting to a Kelvin-Voigt model.
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Affiliation(s)
- Adeel Ahmad
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 405 North Mathews Avenue, Urbana, IL, 61801 USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 1406 West Green St, Urbana, Illinois 61801, USA
| | - Jongsik Kim
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 405 North Mathews Avenue, Urbana, IL, 61801 USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 1406 West Green St, Urbana, Illinois 61801, USA
| | - Nahil A. Sobh
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 405 North Mathews Avenue, Urbana, IL, 61801 USA
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Mathews Ave, Urbana, Illinois 61801, USA
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 1206 West Green St, Urbana, Illinois 61801, USA
| | - Nathan D. Shemonski
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 405 North Mathews Avenue, Urbana, IL, 61801 USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 1406 West Green St, Urbana, Illinois 61801, USA
| | - Stephen A. Boppart
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 405 North Mathews Avenue, Urbana, IL, 61801 USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 1406 West Green St, Urbana, Illinois 61801, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, 1304 West Springfield Avenue, Urbana, Illinois 61801, USA
- Department of Internal Medicine, University of Illinois at Urbana-Champaign, 506 South Mathews Ave, Urbana, Illinois 61801, USA
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6
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Kennedy BF, Koh SH, McLaughlin RA, Kennedy KM, Munro PRT, Sampson DD. Strain estimation in phase-sensitive optical coherence elastography. BIOMEDICAL OPTICS EXPRESS 2012; 3:1865-79. [PMID: 22876350 PMCID: PMC3409705 DOI: 10.1364/boe.3.001865] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Revised: 06/28/2012] [Accepted: 07/12/2012] [Indexed: 05/02/2023]
Abstract
We present a theoretical framework for strain estimation in optical coherence elastography (OCE), based on a statistical analysis of displacement measurements obtained from a mechanically loaded sample. We define strain sensitivity, signal-to-noise ratio and dynamic range, and derive estimates of strain using three methods: finite difference, ordinary least squares and weighted least squares, the latter implemented for the first time in OCE. We compare theoretical predictions with experimental results and demonstrate a ~12 dB improvement in strain sensitivity using weighted least squares compared to finite difference strain estimation and a ~4 dB improvement over ordinary least squares strain estimation. We present strain images (i.e., elastograms) of tissue-mimicking phantoms and excised porcine airway, demonstrating in each case clear contrast based on the sample's elasticity.
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Affiliation(s)
- Brendan F. Kennedy
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Sze Howe Koh
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Robert A. McLaughlin
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Kelsey M. Kennedy
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Peter R. T. Munro
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - David D. Sampson
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
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7
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Lamouche G, Kennedy BF, Kennedy KM, Bisaillon CE, Curatolo A, Campbell G, Pazos V, Sampson DD. Review of tissue simulating phantoms with controllable optical, mechanical and structural properties for use in optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2012; 3:1381-98. [PMID: 22741083 PMCID: PMC3370977 DOI: 10.1364/boe.3.001381] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 04/30/2012] [Accepted: 05/04/2012] [Indexed: 05/18/2023]
Abstract
We review the development of phantoms for optical coherence tomography (OCT) designed to replicate the optical, mechanical and structural properties of a range of tissues. Such phantoms are a key requirement for the continued development of OCT techniques and applications. We focus on phantoms based on silicone, fibrin and poly(vinyl alcohol) cryogels (PVA-C), as we believe these materials hold the most promise for durable and accurate replication of tissue properties.
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Affiliation(s)
- Guy Lamouche
- National Research Council Canada, 75 de Mortagne, Boucherville, Québec, J4B6Y4, Canada
- These authors contributed equally to this paper
| | - Brendan F. Kennedy
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
- These authors contributed equally to this paper
| | - Kelsey M. Kennedy
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | | | - Andrea Curatolo
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Gord Campbell
- National Research Council Canada, 75 de Mortagne, Boucherville, Québec, J4B6Y4, Canada
| | - Valérie Pazos
- National Research Council Canada, 75 de Mortagne, Boucherville, Québec, J4B6Y4, Canada
| | - David D. Sampson
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
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8
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Li C, Guan G, Reif R, Huang Z, Wang RK. Determining elastic properties of skin by measuring surface waves from an impulse mechanical stimulus using phase-sensitive optical coherence tomography. J R Soc Interface 2012; 51:908-12. [PMID: 22048946 DOI: 10.1109/tuffc.2004.1320751] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023] Open
Abstract
The mechanical properties of skin are important tissue parameters that are useful for understanding skin patho-physiology, which can aid disease diagnosis and treatment. This paper presents an innovative method that employs phase-sensitive spectral-domain optical coherence tomography (PhS-OCT) to characterize the biomechanical properties of skin by measuring surface waves induced by short impulses from a home-made shaker. Experiments are carried out on single and double-layer agar-agar phantoms, of different concentrations and thickness, and on in vivo human skin, at the forearm and the palm. For each experiment, the surface wave phase-velocity dispersion curves were calculated, from which the elasticity of each layer of the sample was determined. It is demonstrated that the experimental results agree well with previous work. This study provides a novel combination of PhS-OCT technology with a simple and an inexpensive mechanical impulse surface wave stimulation that can be used to non-invasively evaluate the mechanical properties of skin in vivo, and may offer potential use in clinical situations.
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Affiliation(s)
- Chunhui Li
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
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9
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Sarantopoulos A, Beziere N, Ntziachristos V. Optical and Opto-Acoustic Interventional Imaging. Ann Biomed Eng 2012; 40:346-66. [DOI: 10.1007/s10439-011-0501-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 12/23/2011] [Indexed: 12/20/2022]
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10
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Li C, Guan G, Reif R, Huang Z, Wang RK. Determining elastic properties of skin by measuring surface waves from an impulse mechanical stimulus using phase-sensitive optical coherence tomography. J R Soc Interface 2011; 9:831-41. [PMID: 22048946 DOI: 10.1098/rsif.2011.0583] [Citation(s) in RCA: 137] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The mechanical properties of skin are important tissue parameters that are useful for understanding skin patho-physiology, which can aid disease diagnosis and treatment. This paper presents an innovative method that employs phase-sensitive spectral-domain optical coherence tomography (PhS-OCT) to characterize the biomechanical properties of skin by measuring surface waves induced by short impulses from a home-made shaker. Experiments are carried out on single and double-layer agar-agar phantoms, of different concentrations and thickness, and on in vivo human skin, at the forearm and the palm. For each experiment, the surface wave phase-velocity dispersion curves were calculated, from which the elasticity of each layer of the sample was determined. It is demonstrated that the experimental results agree well with previous work. This study provides a novel combination of PhS-OCT technology with a simple and an inexpensive mechanical impulse surface wave stimulation that can be used to non-invasively evaluate the mechanical properties of skin in vivo, and may offer potential use in clinical situations.
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Affiliation(s)
- Chunhui Li
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
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Bisaillon CÉ, Dufour ML, Lamouche G. Artery phantoms for intravascular optical coherence tomography: healthy arteries. BIOMEDICAL OPTICS EXPRESS 2011; 2:2599-613. [PMID: 21991552 PMCID: PMC3184869 DOI: 10.1364/boe.2.002599] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 08/10/2011] [Accepted: 08/11/2011] [Indexed: 05/19/2023]
Abstract
We present a method to make phantoms of coronary arteries for intravascular optical coherence tomography (IV-OCT). The phantoms provide a calibrated OCT response similar to the layered structure of arteries. The optical properties of each layer are achieved with specific concentrations of alumina and carbon black in a silicone matrix. This composition insures high durability and also approximates the elastic properties of arteries. The phantoms are fabricated in a tubular shape by the successive deposition and curing of liquid silicone mixtures on a lathe setup.
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